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<body>
  <p>btn按钮bst4</p>
  <a name="" id="" class="btn btn-primary" href="#" role="button">按钮</a>
  <br/>
  <div class="well">
    <p>btn按钮bst4样式</p>
    <button class="btn btn-default">按钮</button>
    <button class="btn btn-primary">按钮</button>
    <button class="btn btn-danger">按钮</button>
    <button class="btn btn-warning">按钮</button>
    <button class="btn btn-info">按钮</button>
    <br/>
    <p>btn按钮bst4功能</p>
    <a href="www.baidu.com" class="btn btn-primary">断网测试</a>
    <input class="btn btn-info" type="submit" value="按钮提交">
    <br/>
    <p>btn按钮bst4大小</p>
    <button class="btn btn-warning btn-lg">按钮lg</button>
    <button class="btn btn-info">按钮md</button>
    <button class="btn btn-primary btn-sm">按钮sm</button>
    <button class="btn btn-danger btn-xs">按钮xs</button>
    <br/>
    <p>btn按钮block</p>
    <button class="btn btn-primary btn-block">按钮</button>

    <div class="btn-group">
      <button class="btn btn-default">按钮</button>
      <button class="btn btn-default">按钮</button>
      <button class="btn btn-default">按钮</button>
    </div>
  </div>

  <div class="btn-toolbar">
    <div class="btn-group btn-group-lg">
      <button class="btn btn-default">按钮</button>
      <button class="btn btn-default">按钮</button>
      <button class="btn btn-default">按钮</button>
    </div>
    <div class="btn-group">
      <button class="btn btn-default">按钮</button>
      <button class="btn btn-default">按钮</button>
      <button class="btn btn-default">按钮</button>
    </div>
    <div class="btn-group-sm">
      <button class="btn btn-default">按钮</button>
      <button class="btn btn-default">按钮</button>
      <button class="btn btn-default">按钮</button>
    </div>
  </div>
  <p>
    <div class="btn-group-vertical">
      <button class="btn btn-default">按钮</button>
      <button class="btn btn-default">按钮</button>
      <button class="btn btn-default">按钮</button>
    </div>
  </p>
</body>
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